In the larger block sizes, it'd be quick to whip up. As smaller blocks they'd be great for a block exchange with your quilting bee or guild.

General Instructions

All seams are 1/4".

Several abbreviations are used:

SA - seam allowance

QST - quarter square triangle

RST - right sides together

When instructed to press, first press the pieced unit flat to set the seam. Then open the patch, pressing from the front. Seam allowances are pressed to the dark fabric unless otherwise noted.

The instructions that follow are for a traditionally pieced block, though your Double Pinwheel could easily and efficiently be paper pieced. (Click here for those instructions and the free downloadable paper piecing patterns.)

Step 1: Cut the fabric patches

Double Pinwheel block design

The measurements in the chart below are exact. If your quarter inch seam allowance is reliably accurate, use these measurements.

All the numbers in the chart below represent squares (to make the chart easier to read).

Personally, I prefer to make quarter square triangles (QST) with oversized patches, sew them, and then trim to the perfect size.

So if a patch for #1 is 4-1/4", I added a quarter inch and cut it 4-1/2" x 4-1/2". Necessary subcuts are at the end of each row for #1-#3.

Stitch as directed in the instructions.

After sewing the QSTs, there's a chart so that you can check that they are accurate, trimming if needed.

Cutting Chart for aDouble Pinwheel Quilt Block

~Traditional Piecing ~

Patch

Fabric

Qty

Finished Block Size

SubCut

3"

4"

5"

6"

8"

1

A

1

2¾"

3¼"

3¾"

4¼"

5¼"

2

B

1

2¾"

3¼"

3¾"

4¼"

5¼"

3

C

2

2⅜"

2⅞"

3⅜"

3⅞"

4⅞"

Unfinished Block Size

3½"

4½"

5½"

6½"

8½"

na

Grid Size

1½"

2"

2½"

3"

4"

na

My go-to thread for all my piecing is...

After the sub-cutting they look like this.

Step 2: Assemble the units

With RST, align the edges of one #1/white dot and #2/blue dot patch. So that the patches end up in the proper position, stitch with #2/blue on top and feed the blunt edge into your sewing machine first.

That red arrow is pointing towards my anchor cloth.I always use one.

Press the unit flat. Then press it open with the seam allowance towards #2/blue dot.

The edges of this stitched pair should be straight and even.

This edge is nice and straight

With RST, align the long edge of this pieced unit with the long edge of the #3/yellow triangle.

Stitch.

The red arrow below points to my anchor cloth.

Press the unit flat to set the seam. Then press open with the seam allowance towards the #3/yellow patch.

Repeat for the three remaining units.

The QSTs look like this before trimming.

For this 6" finished sample block, this unit should measure 3-1/2" square. Trim if needed.

Check for Accuracy

If you used the exact size for cutting the original squares, measure your block to confirm it is the correct size (see 'Size, edge-to-edge' in the chart below).

Check for Accuracy

Whirlwind QST units

Finished Block Size

3"

4"

5"

6"

8"

Center (Midpoint)

1"

1¼"

1½"

1¾"

2½"

Size, edge-to-edge

2"

2½"

3"

3½"

4½"

If you added a 1/4" to the dimensions to create generous squares, it's time to trim our patches to 3-1/2" for our 6" finished sample. Use the 'Center (Midpoint)' measurement from the chart above.